Event in not triggered in parallel processing

Question

Hello ABAP community,
i am playing around with ABAP OO and doing my first lessons in parallel processing. I am trying to comibine parallel processing (CALL FUNCTION STARTING NEW TASK) with the ABAP OO concept of events.
The idea is to create many instances of a class (RECEIVER_CLASS) and call them in parallel. I want to catch the result of each CALL with the RECEIVE statement and trigger an event to inform the caller class about the finished function/class. In this case a method RESULT is called. I want to access the data of the event via the implicit parameter SENDER (according to online documentation).
Here you can find a simple report. The event seems to be triggerd but the method RESULT will never be called.
REPORT  zcra_parallel2.
*       CLASS receiver_class DEFINITION
CLASS receiver_class DEFINITION.
  PUBLIC SECTION.
    METHODS:
      start IMPORTING value(i_taskname) TYPE char8,
      receiver1 IMPORTING value(p_task) TYPE clike.
    <b>EVENTS:
      finished.</b>
ENDCLASS.                    "receiver_class DEFINITION
*       CLASS receiver_class IMPLEMENTATION
CLASS receiver_class IMPLEMENTATION.
  METHOD start.
    CALL FUNCTION 'ZZ_CRA1' STARTING NEW TASK i_taskname
      CALLING me->receiver1 ON END OF TASK
      EXPORTING
        mytask = i_taskname.
    IF sy-subrc = 0.
      WRITE: /, i_taskname, ' TASK started...'.
    ENDIF.
  ENDMETHOD.   "start
  METHOD receiver1.
    DATA:
      myinfo TYPE TABLE OF zcra1.
    RECEIVE RESULTS FROM FUNCTION 'ZZ_CRA1'
      TABLES my_itab = myinfo.
    <b>RAISE EVENT finished.</b>
  ENDMETHOD.                                                "receiver1
ENDCLASS.                    "receiver_class IMPLEMENTATION
*       CLASS x DEFINITION
CLASS caller DEFINITION.
  PUBLIC SECTION.
    DATA:
      y_ref TYPE REF TO receiver_class,
      z_ref TYPE REF TO receiver_class.
    METHODS:
      constructor,
      <b>result FOR EVENT finished OF receiver_class.</b>
ENDCLASS.                    "callerx DEFINITION
*       CLASS callerx IMPLEMENTATION
CLASS caller IMPLEMENTATION.
  METHOD constructor.
    SET HANDLER: me->result FOR ALL INSTANCES.
    CREATE OBJECT: y_ref, z_ref.
    CALL METHOD y_ref->start( 'WAIT1' ).
    CALL METHOD z_ref->start( 'WAIT2' ).
  ENDMETHOD.                    "constructor
  <b>METHOD result.
    WRITE: /, 'EVENT TRIGGERD!'.
  ENDMETHOD.</b>                    "result
ENDCLASS.                    "callerx IMPLEMENTATION
DATA:
  mycaller TYPE REF TO caller.
START-OF-SELECTION.
  CREATE OBJECT mycaller.
Thanks for any help!

Answer 1

Here is the sample program that I'm working with.  I took your code and changed some things in order to get it working on my system(46c).   Maybe this will help you.
report zrich_0003 .
data:    session(1) type c.
data:    event_fired(1) type c.
*       CLASS receiver_class DEFINITION
class receiver_class definition.
  public section.
    methods:     trigger_event,
                 start importing value(i_taskname) type char8,
                 receiver1 importing value(p_task) type c .
    events:      finished.
endclass.
*       CLASS receiver_class IMPLEMENTATION
class receiver_class implementation.
  method start.
    data: messtab type table of bdcmsgcoll,
          bdcdata type table of bdcdata .
    call function 'ABAP4_CALL_TRANSACTION' starting new task i_taskname
*      calling me->receiver1 on end of task
       performing reciever on end of task
        exporting        mytask = i_taskname
                 tcode                         = 'SM50'
                 mode_val                      = 'N'
                 update_val                    = 'S'
               tables
                 using_tab                     = bdcdata
                 mess_tab                      = messtab.
    wait until session = 'X'.
*    if sy-subrc = 0.
*      write: / i_taskname, ' TASK started...'.
*    endif.
  endmethod.   "start
  method receiver1.
*    data: myinfo type table of zcra1.
*    receive results from function 'ABAP4_CALL_TRANSACTION'
*   tables
*      mess_tab              = messtab.
*    raise event finished.
  endmethod.
  method trigger_event.
    raise event finished.
  endmethod.
endclass.
*       CLASS caller DEFINITION
class caller definition.
  public section.
*    data: y_ref type ref to receiver_class,
*          z_ref type ref to receiver_class.
    methods:
    constructor,
    result for event finished of  receiver_class.
endclass.
*       CLASS caller IMPLEMENTATION
class caller implementation.
  method constructor.
    set  handler: me->result for all instances.
*    create object: y_ref, z_ref.
*    call method y_ref->start( 'WAIT1' ).
*    call method z_ref->start( 'WAIT2' ).
  endmethod.
  method result.
    event_fired = 'X'.
  endmethod.
endclass.
data: y_ref type ref to receiver_class,
      z_ref type ref to receiver_class.
data: mycaller type ref to caller.
start-of-selection.
  create object mycaller.
  create object: y_ref, z_ref.
  call method y_ref->start( 'ZRICH2' ).
  write:/ 'Event Fired:', event_fired.
*       FORM reciever                                                 *
*  -->  TASKNAME                                                      *
form reciever using taskname.
  data: messtab type table of bdcmsgcoll.
  receive results from function 'ABAP4_CALL_TRANSACTION'
       tables
          mess_tab              = messtab.
  session = 'X'.
  call method y_ref->trigger_event.
endform.
Regards,
Rich Heilman